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This study goals to: (1) Produce learning media based on virtual lab applications that is worth for use in class XI learning on the subject of optics, (2) find out how much increase of visual science literacy of grade XI students in Class on the subject of optics by using virtual lab application with a discovery learning approach, and (3) find out how much increase of conceptual understanding of grade XI student in class on the subject of optics by using virtual lab application with a discovery learning. This research is development research with a 4D model design consisting of define, design, develop and disseminate. The subject of this study was students of grade XI science class on second semester Public Senior High School 1 Godean in Academic Year 2020/2021. Define step to perform needs analysis such as analyzing the condition of the school environment, students, curriculum, and learning objectives. The design step of the researchers made a product design of virtual learning media lab optical tools and research instruments. The development step is carried out validation of research products and instruments until conducting limited trials. Disseminate step, researchers disseminate products that have been made through the website. The results obtained indicate that: 1) learning media in the form of virtual optical lab tools with a discovery learning approach using 3D Unity are feasible, 2) virtual lab optical tools media can improve the scientific literacy of high school students in class XI with moderate categories, and 3) virtual optical instrument practicum media can improve students' conceptual understanding on optical instrument material, sub-materials of reflection and refraction with high categories. [ABSTRACT FROM AUTHOR]

Indonesia is one of the largest cocoa (Theobroma cacao L.) producing countries in the world. The production of cocoa produced a waste such as cocoa pod husk that increasing every year and it can be used for producing another valuable product such as sugars. Cocoa pod husk waste contain pectin which has the potential to be used as a substrate for pectinolytic microorganisms to be hydrolyzed into reducing sugar or glucose monomers. In the biotechnological industry, pectin and pectinase are essential macromolecules. They are widely used in the food industry for wine and juice production, clarifying agent and plant tissue maceration. This study was conducted to obtain optimal conditions for the production of pectinase enzyme by Kitasatospora sp. using cocoa pod husk in 1.5 L bioreactor tank. Testing is carried out in several parameters: agitation and aeration. From two parameters used, the one that produces the highest pectinase activity value is selected by using OFAT (One Factor at A Time) method. Beginning of the experiment Agitation was set to 100, 150, 200, 250, 300, 350, 400 rpm and the variation of Aeration ranged from 1 to 3 lpm. Testing the activity of the pectinase enzyme was carried out using the Dinitrosalicylic acid (DNS) method. As the result, the production of pectinase enzyme by the variations of agitation gives the highest pectinase activity value of 3.92 U/mL at 200 rpm, 2 lpm for 144 h. [ABSTRACT FROM AUTHOR]

Covid-19 outbreak had a great impact on the demand of ventilator. Thus, researches are concern to find solutions to fulfill the high demand within short time. 3D printing has been one of the promising solutions to build complex structure rapidly. However, to achieve the best quality and optimal production time, further research is needed. In this research, an experiment of 3D printed flow restrictor with various parameters is observed. PLA (Polylatic Acid) is chosen as the filament with 4 responses which are length, inside diameter, outside diameter and printing duration. The experiment is designed based on Taguchi method, since there are 4 responses the PCR-TOPSIS method is used to obtain the optimum parameter setting. Then, the confirmation experiment is required to verify that the parameter is valid and optimal. The result of this research which is the optimum parameter are 225°C nozzle temperature, 75% infill density, and 0,1 mm layer height. [ABSTRACT FROM AUTHOR]

A major earthquake occurred in Yogyakarta, Indonesia, on May 27th, 2006, with a magnitude of 5.9 Richter Scale and a depth of 33 km. The earthquake, which lasted about 60 minutes, damaged 2900 school buildings in the Yogyakarta area. Bantul Regency suffered the most losses due to this earthquake. The preparedness of the school community in Bantul must be organized as early as possible, to reduce the earthquake risk that possibly occurs in the future. This study aims to assess the preparedness index of the Muhammadiyah school community in Tirtonirmolo Village, Bantul Regency. There are 3 schools assessed, consisting of 1 SD (Primary School), 1 SMP (Junior High School), and 1 SMA (High School). The assessment uses primary data taken directly from the surveys on the physical, institution, teacher, and student preparedness. This study considers 5 parameters of preparedness, namely physical, knowledge, policies, emergency response plans, and resource mobilization parameters. The preparedness indexing is determined by scoring and weighting using the Analytic Hierarchy Process method. The result shows that SD Muhammadiyah Mrisi and SMA Muhammadiyah Kasihan met the high level of school community preparedness, with an index of 80.7 and 81.0, while SMP Muhammadiyah Kasihan met the moderate level of school community preparedness, with an index of 66.5. All schools have good physical preparedness as indicated by the fulfillment of the school building as an earthquake-resistant structure. In addition, several programs that can be carried out to improve the school community preparedness level of SMP Muhammadiyah Kasihan have been recommended. [ABSTRACT FROM AUTHOR]

In the current investigation, a modified process combining pre-annealing and post-hydrothermal treatments has been applied on the as-dried TiO2 nanotubes derived from alkaline route of TiO2 P25 nanoparticles in 10 M NaOH solution. The combined treatment is purposely aimed at enhancing the nanocrystallinity of anatase TiO2, while at the same time maintaining the integrity of the nanotube hollow structures. The detail of the structure, morphology and crystallinity of the resulting nanotubes were examined by XRD, SEM and TEM, while the optical properties of nanotubes were investigated by UV-visible spectroscopy. For the nanotube samples which have been previously annealed at 300 °C, the crystallite size of anatase TiO2 in nanotubes increased from 17.20 to 18.30 nm after being subjected to post-hydrothermal treatment at 100 to 150 °C. The band gap energy (Eg) of the resulting nanotubes is inversely proportional to the crystallite size of anatase phase where the lowest value of 3.21 eV was obtained from the TiO2 nanotube sample with the biggest crystallite size of 18.30 nm. [ABSTRACT FROM AUTHOR]

Intra uterine insemination (IUI) as one of the treatment for infertility, persists low success rate. A factor that contributes to the unsuccessful of IUI is sperm preparation, performed through Swim-up (SU) and Density Gradient Centrifugation (DGC) methods. Furthermore, studies have shown that Alpha Lipoic Acid (ALA) is a potent antioxidant that could enhance the sperm motility and protect the DNA integrity of the sperm [1]. This study is aimed to re-evaluate the efficiency of the DGC and SU methods in selecting sperm before being transferred for IUI by the supplementation of ALA based on the sperm DNA integrity. Semen samples were obtained from 13 men from partners of women who are infertile (normozoospermia) and underwent IUI. Semen analysis based on the guideline of World Health Organization (WHO) 2010 was performed to measure the sperm motility and velocity, before and after sperm preparation. Then, samples were incubated with Alpha Lipoic Acid (ALA) in 0.625 mg (ALA 1), 1.25 mg (ALA 2) and 2.5 mg (ALA 3). The Sperm Chromatin Dispersion (SCD) test was performed to evaluate the sperm DNA Fragmentation Index (DFI). The percentage of motile sperm was higher in prepared sperm (post-DGC and post-SU) than in whole semen. Furthermore, the percentage of motile sperm was higher in post-DGC compared to post-SU. The level of DFI after the supplementation of ALA was decreased in prepared sperm compared to the whole semen. ALA was proved capable to select the better sperm quality with decreased sperm DNA fragmentation of prepared sperm in the all of DFI category. [ABSTRACT FROM AUTHOR]

Gelatin is one of the most common food additives in the food and beverage industry. Gelatin is generally made of leather or pig bones, causing concerns about the halal and safety of its product. Mackerel fish bone (Scomberomorus commerson) is a waste fish that has not been utilized well and it contains 18.6% of collagen so that it can be made into gelatin. The purpose of this research is to know the relation between HCl concentration with physical and chemical characteristics of gelatin and to know the best HCl concentration for gelatin production. Based on the physical and chemical analysis of gelatin, it is known that the concentration of hydrochloric acid influences the yield, viscosity, gel strength and pH produced. The higher HCl concentration there will be decrease in the pH value, gel strength, viscosity and protein. The yield will rise to the optimum point then decrease with respect to the high HCl concentration. Gelatin with 2% HCl concentration was the best treatment, with pH value 3.83, viscosity 3.65cP, gel strength 190.50 blooms which fulfilled British Standard, yield 10.16%, protein content 43.34%. It has functional group such as amino acids glycine, proline and hydroxyproline and 15 other amino acids, the gelatin group uptake in the region of amide wave numbers A, amides I, II and III, with a gelatin molecular weight of 290.35 g/mol. [ABSTRACT FROM AUTHOR]